This invention relates to novel benzolactam compounds which are useful as pharmaceuticals, particularly as brain function-improving drugs, or isomers thereof as well as salts thereof, their pharmaceutical uses and the intermediates for their synthesis.
In European Patent Publication No. 125056A, European Patent Publication No. 156455A, British Patent Publication No. 2143816A and Japanese Patent Unexamined Publication (Kokai) No. 148171/1986, there are disclosed 3-(1-carboxyalkyl)amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-ace tic acid derivatives which possess antihypertensive actions. In British Patent Publication No. 2103614A and European Patent Publication No. 166357A, there are reported 3-amino-2-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine derivatives which possess antihypertensive actions or cholecystokinin antagonistic actions.
A number of psychotropic agents and antidemential agents called consciousness disturbance-improving drugs, antiamnesiac drugs, cognition-activating drugs or nootropics have been developed so far in order to improve consciousness-disturbance, remembrance-disturbance, cognition-deterioration, hypobulia and various dementia which are caused by brain function disturbance or brain organ disturbance. Any of those drugs, however, are not necessarily satisfactory in the aspect of their efficacy, duration of their actions and their side effects.
As the result of intensive research conducted by the present inventors to solve the above-mentioned problems, they found that novel benzolactam compounds exhibit an improving effect on various experimental amnesia models, socalled antiamnesia actions, which led to the accomplishment of the present invention.